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The majority of medications a woman has taken will be secreted into her breast milk. Research involving animal brains has raised concerns over the damage breastfeeding mothers who take antiepileptic drugs may be causing on their infant's neurological development. Researchers from the Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) Study Group have revealed that children breastfed by mothers taking antiepileptic drugs did not suffer adverse effects on their cognitive function.

"Our study does not provide a final answer, but we recommend breastfeeding to mothers with epilepsy, informing them of the strength of evidence for risks and benefits,” Dr. Kimford J. Meador lead researcher from Stanford University said in a statement. ”Our recommendation is based on the known positive effects of breastfeeding, the results of our study, an unsubstantiated speculative risk, and theoretical reasons why breastfeeding when taking AEDs would not offer additional risk."

Meador and his colleagues evaluated the cognitive development of 181 children at the age of 6, including both their breastfeeding and IQ data. Around 43 percent of the children participating in the study were breastfed for an average of seven months. Preliminary results showed no IQ difference among children who were breastfed and those who were not at the age of 3. However, the research team noted that school performance and adult abilities based on IQ are more predictive at the age of 6.

At 6 years old, children breastfed by epileptic mothers taking valproic acid (valproate) in high doses were likely to score an IQ lower by seven to 13 points compared to children whose mother did not antiepileptic drugs. In spite of this minimal difference between IQ scores, no adverse effects on cognitive function were detected. Higher child IQ was also associated with higher maternal IQ and children were more likely to have higher IQ if they were breastfed.

"The most conservative interpretation of these results is that breastfeeding is safe for women taking these AEDs as monotherapy and should be strongly encouraged by all participants in their care, including neurologists, pediatricians, obstetricians and allied health professionals." Dr. Cynthia L. Harden of North Shore-Long Island Jewish Health System said in an accompanying editorial.

Meador also noted that this study is an ongoing investigation of neurological development for children of epileptic mothers treated with antiepileptic drugs. Due to these preliminary results and the fact that antiepileptic drugs help 70 percent of people with epilepsy control their seizures, the research team suggests that expecting mothers continue their treatment with help from their physician.